Shah (Imam) Mosque in Isfahan and Vakil Mosque in Shiraz were constructed by the orders of Shah Abbas Safavi and Karim Khan Zand as new mosques for their capitals. These two constructions are categorized in the Isfahan architectural school. With comparing of two mosques, differences in architecture can be discovered; while the features listed for Isfahan school cannot be the explanation for it. With considering that the time between constructions of two buildings is not so long, likewise the continuation of cultural elements of Iran from the Safavid to Zand, these dissimilarities are the main question of this paper. The hypothesis of this article is that the governmental method and characterization of two employers is the most important reason of these dissimilarities. For examination of the hypothesis, the historical research method and some tactics such as field studies, visual observations and documentary studies were used. With Comparing of findings, consequential evidences were extracted and evaluated.Therefore the architectural elements differences including domes, minarets, porches, decorations and their humanity’s proportions for obtaining the causes of these differences through description of governmental method and characterization of two employers were explicated. The results showed that the governmental ambitions of Shah Abbas Safavi (the Great King) in the Isfahan Shah mosque, presented by elements such as four high minarets, great dome and four porches, completely covered mosaic surfaces and its grandeur. While the governmental method and ambitions of Karim Khan Zand (Vakiloroya: the People Representative) in the Shiraz Vakil Mosque presented by non-existent minaret and dome, only two porches, brief mosaics and its superior humanity’s proportions.